Data Package on the Blackberry Storm

Hi. My friend has the original Blackberry Storm, and no longer wants it. They were going to give it to me. I currently have the enV3, and I pay $59.99/mo for 450 minutes/unlimited texting, and $9.99/mo for the data package. My question is, if I activated the Storm, would I have to upgrade my data package to the $29.99? I am unable to afford the $29.99/mo plan, and I wouldn't need unlimited data with the phone. I know a package is required, but I am wanting to know if I can stick with the package I currently have. Thank you!